About reed beds
It has been known for many years that a reed bed will clean contaminated waters. This cleaning process relies on naturally occurring bacteria within the reed bed feeding upon the harmful materials in the effluents as it slowly filters through the bed.
Recent reseach has looked into the best ways of constructing reed beds. There are basically two designs, vertical flow and horizontal flow. These can be used to treat domestic effluents, landfill leachate, stormwaters, winery effluents, farmyard runoffs etc.
Both types of reed bed usually employ a settlement tank prior to any treatment taking place. The size of the tank required is determined by the flow in litres per day. Allowing the raw effluent to stand means it gives solids a chance to settle out. The solid material needs to be removed on a regular basis eg. once a year to prevent any reduction in holding capacity.
A correctly designed and installed reed bed allows effluents to be treated to a very high standard.
What do reed beds do to effluents?
They will remove organic materials which would otherwise strip oxygen from the water and in their breakdown prevent light penetration, both of which can cause the death of aquatic plants and animals. They also reduce nitrates and phosphates which cause algal blooms and very importantly remove pathogens and other pollutants such as heavy metals.
Freshly planted reed bed.
Hard working reed bed.
A matured reed bed.